Mexican Gray Wolf Reintroduction Program

“The Mexican gray wolf remains the most endangered wolf in the world. Despite decades of effort to re-introduce these intelligent, family-oriented creatures into the wild, just over 80 Mexican gray wolves live in their natural habitat. That’s simply not enough to ensure the wolves will survive outside of captivity over the long-term.”

-John Linehan, Zoo New England President and CEO

Since 1998, Zoo New England has been committed to re-introducing Mexican gray wolves into the wilds of the American Southwest, where they once lived in large numbers. Stone Zoo is one of about 50 facilities across the country and in Mexico participating in the Mexican Wolf Species Survival Plan (SSP). We have overseen births of these rare animals at Stone Zoo and collaborated closely with other facilities to transfer and receive wolves on their journey to being re-introduced to the wild.

Overview

The Mexican gray wolf (Canis lupus baileyi), also known as “el lobo” in Spanish, was once common throughout western Texas, southern New Mexico, central Arizona and northern Mexico. But by the mid-1900s they were eliminated from the wild in the U.S., victims of eradication efforts to prevent them from preying on livestock. They survived here only in small captive populations, and in Mexico their population also dwindled dramatically.

Great strides have been made to grow the Mexican gray wolf population and reintroduce them into the wild. In 1976, they were listed as endangered under the Endangered Species Act. The Mexican wolf recovery team was formed and a conservation and survival plan was established in 1979. In 1998, Zoo New England joined the Mexican Wolf Species Survival Plan (SSP), a consortium of institutions working together to breed the captive wolves for reintroduction and recovery in the Southwest.

Mexican gray wolves weigh between 50-80 pounds and are about 5 feet long. Their coat is often mottled or patchy and varies from gray and black to brown and buff. The wolves have complex social behavior, living in tightly organized packs, communicating through howling vocalizations, body posturing and scent marking. These animals work effectively together to adapt to most environments where there is prey, which includes deer, jackrabbit, mice and peccary.

Into the wild

Since 1998, Zoo New England has participated in the Mexican Wolf Species Survival Plan (SSP) – a group of institutions including the U.S. Fish and Wildlife Service, state agencies, several zoos and other partners – all working together to reintroduce captive-bred wolves in the Southwest wilderness. We’re thrilled that the wild Mexican wolf population is slowly increasing.

Following the recommendation of the Mexican Wolf SSP, in 2011 two wolves born at Stone Zoo were relocated to facilities in Mexico. In 2012, the remaining two wolves at Stone Zoo were transferred to the Oklahoma City Zoo and Botanical Garden, which sent five male wolves to Stone Zoo in exchange. Months of careful planning and coordination amongs institutions is required to successfully manage the moves and monitor the wolves’ adjustments to their new homes.

In captivity, close bonds between wolves and keepers are avoided because, ultimately, the wolves’ survival in the wild depends on active avoidance of human contact. The animals cannot become reliant on people for food. Though wolves don't lose their natural instincts in captivity, their hunting skills need to be honed before they are released into the wild. Wolves that are slated for release are sent to large pre-release centers with some level of native prey. Typically, these wolves and their offspring are released into the wild together as a pack.

Back from the brink, slowly

Nearly extinct by the mid-1900s, the wild Mexican Gray Wolf population is slowly coming back from the brink of extinction through the work of the Mexican Wolf SSP and other organizations. Here are some positive signs of progress:

The U.S. Fish and Wildlife Service reports counted at least 83 Mexican wolves in the wild in Arizona and New Mexico at the end of 2013, a 10 percent increase over the 2012 count of 74 wolves. This is the third year of a greater than 10 percent increase in the wolf population.

The Mexican wolf population has nearly doubled in the past four years.

All of the wolves currently within the recovery area in Arizona and New Mexico are wild born, a mark of great progress in re-establishing a wild population

The 2013 population count includes 17 wild-born pups that survived through the end of the year, the twelfth consecutive year in which wild-born wolves bred and raised pups in the wild.

While this growth is encouraging, re-establishing the Mexican gray wolf population is a slow and complex process. For instance, a delicate balance must be maintained between re-introducing the wolves into their natural range and preventing their predation on livestock. That’s why Zoo New England is unwavering in its commitment to the future of this rarest of wolves.

Mexican gray wolves at Stone Zoo

In June of 2013, five Mexican gray wolves – all male siblings – made their debut at Stone Zoo. As they stalk the hills of their expansive wooded habitat, these animals are never far from one another, owing to their tight pack behavior. Want to know which wolf is the “Alpha,” or dominant animal, that day? Look for the wolf whose tail is sticking straight up in the air. The one with its tail tucked between its legs is the most subordinate animal. In addition to the howls that echo through the habitat, visitors might hear other vocalizations, such as the whimpering of subordinate wolves as the dominant wolf passes by them.

The Mexican Gray Wolf exhibit is part of Zoo New England’s participation in the Mexican Wolf Species Survival Plan to reintroduce the animals to the wild. “It is our great hope that some day the descendants of Mexican gray wolves that were either born or cared for at Stone Zoo will be successfully reintroduced into the wild,” says Zoo New England President and CEO John Linehan. “Zoo New England is committed to the conservation of this incredible species and is proud of the role we have played in ensuring that these animals have a continued chance of survival in the wild.”